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    <title>Document</title>
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    <script>
      /**
       * 改变 promise 状态       和指定回调函数谁先谁后 ?
       *
       *  resolve/reject/throw     then/catch
       */
      let p = new Promise((resolve, reject) => {
        //1. 先改变状态, 再指定回调
        // resolve("OK");

        //2. 先指定回调, 再改变状态   这种场景较多
        setTimeout(() => {
          resolve("OK");
          console.log(111);
        }, 1000);
      });

      p.then(
        (v) => {
          console.log(v);
        },
        (r) => {
          console.log(r);
        }
      );
    
      console.log(222);
        
    </script>
  </body>
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